It is known in the art to record a series of picture signals on a moving magnetic tape and subsequently reproduce the picture signals at essentially the same rate of recording to create a motion picture on a video or television screen for visual observation. My patent application Ser. No. 668,348, now U.S. Pat. No. 3,051,777, describes means for recording a video signal of a single frame or screen sweep of the video scanning beam of a camera or flying spot scanner. The video signal may be reproduced thereafter and used to provide a still image picture on a video monitor screen.
In U.S. Pat. No. 2,494,441, a method and an apparatus are disclosed for obtaining the average or mean dimensions of small particles by counting pulses generated in scanning a large number of small particles. In this particular disclosure, it is necessary to mathematically calculate the average or mean particle size and possibly the area covered by the particles by using mathematical formulas. However, it is not possible to specifically pick out a particular particle and measure its size or area directly by using this prior art method and apparatus.
In U.S. Pat. No. 2,731,202, an apparatus is provided for counting the number of particles appearing in a field of view against a background contrasting in appearance with the particles. In this particular prior art structure, a beam is impinged on the viewing field. Whenever there is a change in the beam intensity, an electrical pulse is produced and counted. That is, this prior art method and apparatus merely provides a simple counting technique. There is absolutely no disclosure for digitizing the image on the field of view to provide its location or the specific dimensions thereof.